This book discusses one of the central problems in the philosophy of law--the question of legal determinacy. Is the law a seamless web or are there gaps? Bix argues that the major re-thinking of the common and "common sense" views about law that have been proposed by various recent legal theories is unnecessary. He offers a reconsideration of the role of language in the law, and the way ideas about language have been used and misused in recent legal theory. He (...) explores in depth the relationship to legal theory of Hart's influential idea of "open texture," Dworkin's interpretative approach to law, and Wittgenstein's philosophy. (shrink)

We present a computational model of dialectical argumentation that could serve as a basis for legal reasoning. The legal domain is an instance of a domain in which knowledge is incomplete, uncertain, and inconsistent. Argumentation is well suited for reasoning in such weak theory domains. We model argument both as information structure, i.e., argument units connecting claims with supporting data, and as dialectical process, i.e., an alternating series of moves by opposing sides. Our model includes burden of proof as a (...) key element, indicating what level of support must be achieved by one side to win the argument. Burden of proof acts as move filter, turntaking mechanism, and termination criterion, eventually determining the winner of an argument. Our model has been implemented in a computer program. We demonstrate the model by considering program output for two examples previously discussed in the artificial intelligence and legal reasoning literature. (shrink)

Much work on legal knowledge systems treats legal reasoning as arguments that lead from a description of the law and the facts of a case, to the legal conclusion for the case. The reasoning steps of the inference engine parallel the logical steps by means of which the legal conclusion is derived from the factual and legal premises. In short, the relation between the input and the output of a legal inference engine is a logical one. The truth of the (...) conclusion only depends on the premises, and is independent of the argument that leads to the conclusion.This paper opposes the logical approach, and defends a procedural approach to legal reasoning. Legal conclusions are not true or false independent of the reasoning process that ended in these conclusions. In critical cases this reasoning process consists of an adversarial procedure in which several parties are involved. The course of the argument determines whether the conclusion is true or false. The phenomenon of hard cases is used to demonstrate this essential procedural nature of legal reasoning. (shrink)

A representation methodology for knowledge allowing multiple interpretations is described. It is based on the following conception of legal knowledge and its open texture. Since indeterminate, legal knowledge must be adapted to fit the circumstances of the cases to which it is applied. Whether a certain adaptation is lawful or not is measured by metaknowledge. But as this too is indeterminate, its adaptation to the case must be measured by metametaknowledge, etc. This hierarchical model of law is quite well-established and (...) may serve well as a basis for a legal knowledge system. To account for the indeterminacy of law such a system should support the construction of different arguments for and against various interpretations of legal sources. However, automatizing this reasoning fully is unsound since it would imply a restriction to arguments defending interpretations anticipated at programming time. Therefore, the system must be interactive and the user''s knowledge be furnished in a principled way. Contrary to the widespread opinion that classical logic is inadequate for representing open-textured knowledge, the framework outlined herein is given a formalization in first order logic. (shrink)

This volume puts leading pragmatists in the philosophy of language, including Robert Brandom, in contact with scholars concerned with what pragmatism has come to mean for the law. Each contribution uses the resources of pragmatism to tackle fundamental problems in the philosophy of language, the philosophy of law, and social and political philosophy. In many chapters, the version of pragmatism deployed proves a fruitful approach to its subject matter; in others, shortcomings of the specific brand of pragmatism are revealed. The (...) result is a clearer understanding of what pragmatism has meant and can mean across these tightly related philosophical areas. The book, then, is itself pragmatism in action: it seeks to clarify its unifying concept by examining the practices that centrally involve it. (shrink)

This paper is a preliminary investigation into the application of the formal-logical theory of normative positions to the characterisation of normative-informational positions, pertaining to rules that are meant to regulate the supply of information. First, we present the proposed framework. Next, we identify the kinds of nuances and distinctions that can be articulated in such a logical framework. Finally, we show how such nuances can arise in specific regulations. Reference is made to Data Protection Law and Contract Law, among others. (...) The proposed approach is articulated around two essential steps. The first involves identifying the set of possible interpretations that can be given to a particular norm. This is done by using formal methods. The second involves picking out one of these interpretations as the most likely one. This second step can be resolved only by using further information (e.g., the context or other parts of the regulation). (shrink)

This paper analyses the logical structure of the balancing of conflicting normative arguments, and asks whether non-monotonic logic is adequate to represent this type of legal or practical reasoning. Norm conflicts are often regarded as a field of application for non-monotonic logics. This paper argues, however, that the balancing of normative arguments consists of an act of judgement, not a logical inference, and that models of deductive as well as of defeasible reasoning do not give an adequate account of its (...) structure. Moreover, it argues that as far as the argumentation consists in logical inferences, deductive logic suffices for reconstructing the argumentation from the internal point of view of someone making normative judgements. (shrink)

This essay investigates the indeterminacy thesis - roughly the claim that the content of authoritative legal materials (such as the texts of constitutions, statutes, cases, rules, and regulations) does not determine the outcome of particular legal disputes. The indeterminacy thesis can be formulated as either "strong" or weak." The strong version of the indeterminacy thesis is demonstrably false, but several weak versions of the thesis are true but lack the radical implications of strong indeterminacy.The strong indeterminacy thesis is the claim (...) that all cases are "hard" cases - or that in any case any conceivable result can be derived from existing legal doctrine. Strong indeterminacy does not hold if there are easy cases - cases in which some outcomes cannot be legally correct. For example, if it were the case that the first paragraph of this abstract did not slander Gore Vidal, then there would be at least one easy case, and strong indeterminacy would be false.Weak versions of the indeterminacy thesis include the claim that important cases are indeterminate, that the law does not necessarily determine outcomes, or that every case could become indeterminate if political conditions supported indeterminacy. These weaker claims may be true, but they lack the critical bite associated with strong indeterminacy.The essay also distinguishes between "determinacy," "indeterminacy," and "underdeterminacy." The law is "determinate" with respect ot a given case if and only if the set of results that can be squared with the legal materials contains only one member. The law is "indeterminate" with respect to a given case if and only if the set of results that can be squared with the legal materials is identical with the set of all imaginable results. The law is "underdeterminate" with respect to a given case if and only if the set of results that can be squared with the legal materials is a nonidentical subset of the set of all imaginable results.This article was first published in 1987, and some of the author's views have been revised in interim. (shrink)